Problem: Multiply, reduce to lowest terms, and write as a mixed number: $ 5\dfrac{3}{5} \times 3\dfrac{3}{4} $
Explanation: $ = \dfrac{28}{5} \times \dfrac{15}{4}$ $ = \dfrac{28 \times 15}{5 \times 4}$ $ = \dfrac{420}{20}$ $ = 21$ $ = 21 0$